The present invention relates to an improved water-borne gas barrier coating composition for polymeric films and rigid, i.e., shaped, containers, and, more particularly, to an improved two-layer coating system which includes a laminar layer mineral in the gas barrier layer and is particularly well suit for spray application. The invention further relates to coated polymeric substrates which exhibit substantially increased gas barrier performance over un-coated polymeric substrates as well as over those which have been coated with any other known gas barrier system.
U.S. Pat. No. 5,700,560 describes a resin composition, and films coated therewith, consisting of a high-hydrogen bonding resin, such as polyvinyl alcohol, and a non-film-forming inorganic laminar compound which provides improved gas barrier properties of the resulting film by increasing the aspect ratio of the inorganic laminar compound.
U.S. Pat. No. 5,571,614 describes a coated polymeric film in which a coating layer is formed from a composition comprising a layer mineral and a cross-linking agent. The coated film additionally comprises a primer layer formed from a copolymer of ethylene with a vinyl monomer which is applied to the film substrate prior to coating with the layer mineral coating.
There is a need for a reliable, economical and environmentally acceptable, i.e., recyclable, coating system for injection stretch blow molded PET bottles, in particular, which will dramatically improve barrier performance such that the bottles can be used for carbonated soft drinks and beer in 12 oz. (33 ml) sizes.